extern bool filemap_range_has_page(struct address_space *, loff_t lstart,
loff_t lend);
-extern bool filemap_range_needs_writeback(struct address_space *,
- loff_t lstart, loff_t lend);
extern int filemap_write_and_wait_range(struct address_space *mapping,
loff_t lstart, loff_t lend);
extern int __filemap_fdatawrite_range(struct address_space *mapping,